d71135e2ca
* made some fix to the ESP32 I2S simple tone example * edit the I2S - simple tone example * edit the I2S - simple tone example * some edit * edit comment * edit * edit * ci(pre-commit): Apply automatic fixes --------- Co-authored-by: pre-commit-ci-lite[bot] <117423508+pre-commit-ci-lite[bot]@users.noreply.github.com>
82 lines
2.2 KiB
C++
82 lines
2.2 KiB
C++
/*
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This example generates a square wave based tone at a specified frequency
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and sample rate. Then outputs the data using the I2S interface to a
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MAX08357 I2S Amp Breakout board.
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I2S Circuit:
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* Arduino/Genuino Zero, MKR family and Nano 33 IoT
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* MAX08357:
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* GND connected GND
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* VIN connected 5V
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* LRC connected to pin 0 (Zero) or 3 (MKR), A2 (Nano) or 25 (ESP32)
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* BCLK connected to pin 1 (Zero) or 2 (MKR), A3 (Nano) or 5 (ESP32)
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* DIN connected to pin 9 (Zero) or A6 (MKR), 4 (Nano) or 26 (ESP32)
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DAC Circuit:
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* ESP32 or ESP32-S2
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* Audio amplifier
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- Note:
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- ESP32 has DAC on GPIO pins 25 and 26.
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- ESP32-S2 has DAC on GPIO pins 17 and 18.
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- Connect speaker(s) or headphones.
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created 17 November 2016
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by Sandeep Mistry
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For ESP extended
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Tomas Pilny
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2nd September 2021
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Lucas Saavedra Vaz (lucasssvaz)
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22nd December 2023
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anon
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10nd February 2025
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*/
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#include <ESP_I2S.h>
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// The GPIO pins are not fixed, most other pins could be used for the I2S function.
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#define I2S_LRC 25
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#define I2S_BCLK 5
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#define I2S_DIN 26
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const int frequency = 440; // frequency of square wave in Hz
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const int amplitude = 500; // amplitude of square wave
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const int sampleRate = 8000; // sample rate in Hz
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i2s_data_bit_width_t bps = I2S_DATA_BIT_WIDTH_16BIT;
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i2s_mode_t mode = I2S_MODE_STD;
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i2s_slot_mode_t slot = I2S_SLOT_MODE_STEREO;
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const unsigned int halfWavelength = sampleRate / frequency / 2; // half wavelength of square wave
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int32_t sample = amplitude; // current sample value
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unsigned int count = 0;
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I2SClass i2s;
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void setup() {
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Serial.begin(115200);
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Serial.println("I2S simple tone");
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i2s.setPins(I2S_BCLK, I2S_LRC, I2S_DIN);
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// start I2S at the sample rate with 16-bits per sample
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if (!i2s.begin(mode, sampleRate, bps, slot)) {
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Serial.println("Failed to initialize I2S!");
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while (1); // do nothing
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}
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}
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void loop() {
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if (count % halfWavelength == 0) {
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// invert the sample every half wavelength count multiple to generate square wave
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sample = -1 * sample;
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}
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// Left channel, the low 8 bits then high 8 bits
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i2s.write(sample);
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i2s.write(sample >> 8);
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// Right channel, the low 8 bits then high 8 bits
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i2s.write(sample);
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i2s.write(sample >> 8);
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// increment the counter for the next sample
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count++;
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}
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